WHAT ARE MUTATIONS?
A mutation, which may arise during replication and/or recombination,
is a permanent change in the nucleotide sequence of DNA. Damaged DNA
can be mutated either by substitution, deletion or insertion of base pairs.
Mutations, for the most part, are harmless except when they lead to cell
death or tumor formation. They can be NEUTRAL like silent mutations,
HARMFUL lor BENEFICIAL
CAUSES OF MUTATIONS:
1) SPONTANEUS MUTATIONS
they occur when mistakes are made during DNA replication or
transcription, in crossing over or by a wrong distribution of
chromosomes in the daughter cells during cellular division. They are
inevitable and casual with no outside influence
2) MUTAGEN/INDUCED MUTATIONS
They are caused by environmental factors. Anything in the
environment that can cause a mutation is known as a MUTAGEN
such as chemicals, radiation or retroviruses.
(smoke, UV radiation, Papillomavirus)
MUTUATIONS CAN OCCUR IN:
1) GERMLINE CELLS MUTATIONS
they occur in gametes. These mutations are espically significant
because they can be transmitted to offspring and every cell in the
offspring will have the mutations.
2) SOMATIC CELLS MUTATIONS:
occur in other cells of the body. These mutations generally have
negative consequences on the human organism but don’t get
transmitted offspring because they are confined to just one cell and
